705

Site number:

705

Authors:

IBC, GGC

Date recorded:

1992/12/31

Reason Sampled:

representative sample of a soil on old till deposits on the valley sides above Lake Vanda; also likely to be a totally undisturbed reference site for contamination studies

Description:

on a sloping glacial bench surface on the north side of Wright Valley, above Lake Vanda and approximately 2km due north of Vanda Station

Altitude:

500 m

Aspect:

S

Slope:

11 °

Climate

Soil climate zone:

central mountain

Estimated mean annual temperature:

-23 °C

Frozen ground depth:

30 ~

Frozen type:

dry frozen

Frozen comment:

~30

Geology

Geological setting:

the deposits on the valley walls in the vicinity of Lake Vanda are commonly described as scree. Close examination showed that there is a series of distinct westward sloping benches (glacial retreat lines) and that the deposits comprise a wide variety of rocks, some of which are basement rocks similar to those occurring down-valley. These deposits are therefore thought to be the deposits from early up-valley glacial advances with relatively minor amounts of detritus originating directly from the Olympus Range. Pale grey till underlies most of the surficial material and may be Peleus Till.

Patterned ground:

Surface weathering or surface features:

moderate staining and oxidation of surface clasts which also exhibit rounding, ventifaction and cavernous weathering

Soil

Soil parent material:

thin intermittent drift over older pale fine textured drift from basement rocks, granites, dolerite and sandstone

Previous disturbance:

nil

Soil weathering stage:

6 3 (Campbell & Claridge 1975)

Soil moisture status:

xerous; the soil surface is occasionally moistened by summer snowfall;

Biological activity: